Sega all the way. I started off with a game gear (Prince of Persia and aliens 3 were 2 of the best platform games ever made) and progressed to a megadrive which i had this game for called populus that was a kind of primitive 'play god' type of thing. Other megadrive favourites include where in the world is Carmen Sandiego (which looking back now was probably quite shit), skitchin', cannon fodder and this doom style game with robots and aliens that i've forgotten the name of that i'm pretty sure was the first game to use 3 dimensions.
I was also really into football games, i remember getting european championship soccer (or whatever it was called) and thinking that there was no way the graphics could ever be topped
My first ever console was an atari 2600, i can't really remember much about it other than i had this flight simulator game that basically involved lining up a square of pixels with another square of pixels and pressing the only button, for some reason it kept me entertained for hours.